Automatic sheet rolling mill



Aug. 6, 1935. A. G. DELANY El AL AUTOMATIC SHEET ROLLING MILL Filed May 4, 1932 6 Sheets-Sheet 1 s m 6: 0 0 Mm mm NM INVENTOR;

A ifielan z/ 611V. HZL Qhfi Z VM v ATTORNEYS Aug. 6 1935. DELANY ET AL 2,010,715

AUTOMATIC SHEET ROLLING MILL Filed May 4, 1932 6 SheetsSheet 2 1935. A. G. DELANY ETAL 2,010,715

' AUTOMATIC SHEET ROLLING MILL Filed May 4, 1932 6 Sheets-Sheet 5 INVENTOR Aug. 6, 1935.

AUTOMATIC SHEET ROLLING MILL 6 Sheets-Sheet 4 Filed May 4, 1952 NMM w m M m 3? m 5 Aug. 6, 1935. A. G. DELANY ET AL 2,010,715

- AUTOMATIC SHEET ROLLING MILL Filed May 4, 1932 6 Sheets-Sheet 5 INVENTOR j A Qfieldn 611V. Hu ghes ATTORNEYS A. G. DELANY El AL 2,010,715

AUTOMATIC SHEET ROLLING MILL Fil ed May 4, 1952 6 Sheets-Sheet 6 r k w Z M W H H 0 no 3 3 M 5 w: =h M, M 5 M w 4 z A 17m a 21) v J M 4 5 n! 8 M Z QJHI I 4 Z 2 M M c Q Z Z 8 w IL Z9 2 3 w w 4 L w w 4! W K J|\ ID El 0 4|,\ 1\( m 8 f E\ E u/ I- N 2 3 8 2/ 4 K K 0 K. m M 2 l H .N/ M L M M 4 w w Ill 1 s H w a 5 5 f 3 Q 0 Aug. 6, 1935.

INVENTOR;

ATTORNEYS ash Patented Augo 6, 1935 UNlTED STATES FATENT OFFICE Hughw, Alabama City, assignments, to The Company, Middletown Ohio Ala., assignors, by mesne American Bolling Mill Ohio, a corporation of Application May i, 1932, Serial No. 609,064

11 Claims.

Our invention relates to a rolling mill for the production of sheets and plates, and has for its object to provide a mill which is entirely automatic in its functioning and is capable of effecting large economies in the cost of the rolled product while at the same time materially increasing the output of rolled product per stand of rolls and insuring accuracy in thickness of the rolled sheets or plates.

Our invention relates more particularly to rolling mills of the type known as two-high or threehigh to which the sheet or plate stock to be rolled is delivered by a feed table; An automatic catcher receives the stock from the rolls and either returns it through the upper or second mill pass of the three-high mill, or passes it over the two-high mill, to the feed table which again delivers the stock to the mill, this back and forth passage of the stock being rapid and continuous for the predetermined number of passes until the finished stock is discharged.

An object of our invention being to render the complete operating cycle of the mill automatic, we contemplate utilizing a time clock controlled delivery of the stock to be rolled to the feed table which has stops to hold back the stock ready for its delivery into the rolling mill automatically responsive to the completion of the preceding rolling cycle which occurs contemporaneously with the return by the screw-down adjustment of the mill rolls to their initial position.

Our invention further contemplates utilizing automatic controls for the catcher which will adapt it to receive the stock. and :return it to or over the mill the requisite number of times until it is ready to be discharged onto a suitable delivery table which delivers it to piling mechanism, not shown.

Our invention further contemplates utilizing automatic means for manipulating the screwdswn mechanism responsive to stock actuated controls, the screw-down being itself adapted, at the completion of each rolling cycle, to con- $701 the delivery of new stock for the next rollirg cycle.

While, in the interest of maximum production, it is desirable to so control the delivery of the stock from the furnace to the rolls that. it is effected immediately upon thev screw-down re- 50 suming initial position, our invention in its broader aspect contemplates the utilization of any automatic stock feed, such for instance as might be accomplished by a periodic delivery thereof d'rect to the rolling mill from the furnace, with 55 a suflicient interval allowed between the succesq sive discharges 0! sheet stock from the furnace to make sure that the preceding rolling cycle has been completed before each new batch of sheet stock is thus delivered to the mill.

Our invention further comprises the novel 5 steps or combination of steps constituting a process or method by which a continuous and automatic rolling operation can be carried out with a single stand of rolls so as to obtain therefrom a production of rolled sheet or plate stock 10 comparable to that heretofore obtained by a sequence of 'roll stands under continuous rolling methods but at greatly reduced cost, due to the relatively small investment in rolling equipment required in the practice of our invention as com- 1 pared with the multiplicity of roll stands and interposed heating furnaces required for the oporation of the continuous rolling process.

Our invention further contemplates so coordinating the automatic control features of the various sheet handling mechanisms which coact with the rolls that the mill is capable of operation almost without idling time, whereby it is capable of rolling the stock in five passes without. reheating and todeliver a production of rolled 25 stock very greatly increased over any production records heretofore attained by manually operated or semi-automatic, rolling mills. By elimihating all skilled labor, except one supervising operator, our mill, despite its higher rate of pro- 30 duction, can be operated at the absolute minimum for labor cost, and due to the screw-down mechanism being mechanically actuated, its successive adjustments of the rolls can be eflected with a speed and degree of accuracy that insures 35 a uniformity in the rolled product not heretofore attainable from manual operated screwdown means.

Our invention further comprises the means for coordinating the functioning of the catcher, screw-down mechanism and the feed table, which respectively form the subject matters of pending applications Serial Nos. 566,230; 586,223; and 605,765, all of which are assigned to the Gulf 45 States Steel Company, the assignee of this appllcation.

Our invention further comprises the novel details of construction, the arrangements of parts, and the methods of operation which are hereinafter more particularly described and claimed, reference being had to the accompanying drawings which form a part of this specification, and in which:-

Fig. 1 is a side view showing the rolls in section,

the catcher and delivery table in side elevation, and parts of the feed table in outline.

Fig. 2 is a detail view partly in section and partly in elevation of the feed table, and time clock control mechanism for the delivery of stock thereto.

Fig. 3 is a diagrammatic layout of the circuits which control the automatic functioning of the feed table.

Fig. 4 is a diagrammatic layout of the circuits which control the automatic functioning of the catcher and the delivery table.

Fig. 5 is a view in side elevation of the roll stand and its mechanically operated automatically controlled screw-down mechanism.

Fig. 6 is a diagrammatic layout of the circuits which control the automatic functioning of the screw-down mechanism.

Similar reference numerals refer to similar parts throughout the drawings.

In the embodiment of our invention illustrated, we have selected a three-high mill as illustrative of a suitable rolling mill for our purposes, the mill comprising a conventional stand I, a lower roll i i, an intermediate roll i2, and an upper rolll3, all having their end bearings suitably guided in the stand and controlled as to the pass clearances between the rolls by screws I having top gears l5 fast thereon and adapted to be turned by the connected gear actuated arm it operated by an arm I! connected to the upper end of a rocker arm l8 journaled at its lower end on a base l9 and having an intermediate connecting rod 20 leading to a crank 2! on a shaft 22 driven by worm gearing 23, 24 from a motor 25 mounted on the base l9 and having a suitable electrically controlled brake 26. The shaft 22 carries a switch trip arm 21 coacting with a series of switches 28, 28a, 28b, etc. The operation of the motor and its automatic control of the adjustments of the screw-down mechanism, which will be hereinafter briefly described, form the subject matter of pending application Serial No. 586,223 hereinabove referred to, to which reference is made for a more complete and detailed description of both the screw-down mechanism and its operation.

In Fig. 2 is shown fragmentally a heating furnace 30 wherein the sheet or plate stock or sheet bars, hereinafter referred to as sheet stock, are heated by any suitable means and from which the sheet stock is delivered by means of a conveyor 3| driven by a belt 32 from a motor 33, the electric circuits for which lead to a standard motor starter box 34 and are adapted to be closed at predetermined time intervals by means of a time clock 35 of any suitable type and character. Opposite the discharge from the furnace we arrange a swinging trip 36 which when engaged by the sheet stock being discharged will open contacts 31 controlling a circuit to the starter box 34 so as to stop the motor 33, after the stock has passed onto a. short endless conveyor 38 driven continuously by the motor 39 so as to feed the sheet stock, as periodically delivered thereto, to the feed table for the mill. As each unit of stock passes out of the furnace it will trip the trip 36 which will act through electrical devices well understood in this art and therefore unnecessary to be illustrated to interrupt the motor circuit. 1

' The feed table, for a more detailed description of which reference is made to. pending application Serial No. 605,765 aforesaid, may be briefly described as comprising an endless conveyor means M, driven by the chains 4! and Ma from a motor 52 continuously in a direction to deliver stock to the mill. The stock received on this conveyor passes forward until arrested by the stops d3 opposite the side matching bars M.

These bars M, arranged on each side of the table, are reciprocated laterally by crank arms 45 on their respective rocker shafts d6 that are so connected to a gear M that as it is rocked by a reciprocable rack bar 68, actuated by the piston of an air motor Q9, these bars move inwardly to match the sheets and then outwardly to release the sheets. Before engaging the stops 43, the stock unit will actuate the trip arm 50 for flag switch 5! of the feed table circuits. The stops 33 are latched in operating position by a cam 52 with which a dog 53 coacts and is adapted to be disengaged from the cam by a trip on piston rod 54 of an air cylinder 55. Air from a three-way valve 56, under control of a magnet 51, flows through the motor 49 to effect the side matching movement of the bars 44 while the stock is held by the stops d3. When magnet 51 is de-energized, the air is reversed, withdrawing the bars 44 and flowing through cylinder 55, where it acts to trip rod 54, raise the dog 53 and release stops 33, whereupon the stock is free to continue its travel toward the mill on the conveyor means $0 until it strikes the second stops which are normally held in operative position by the counter-weighted bell crank 61 through a connecting link 62. A latch 63 normally locks the stops 60 in operative position and is adapted to be tripped to release said stops by means of the piston 64 in a cylinder 65 through which air flows from the threeway valve 66 under control of the magnet 61 and thence to the cylinder 68 where it drives forward the piston '69 carrying the ram head 10 with its pivotally mounted sheet engaging dogs H and trip means for same.

The trip means when the ram head is retracted act to rock the dogs below the path of the stock and when the ram head is advanced spring means 12 will raise the dogs into operative position to engage the stock then held by the stops 60.

The circuits controlling the magnet 61 will not operate until the screw-down mechanism has reset the rolls to initial position when the lower pass is ready to receive the next unit of stock for its first pass through the mill. The plunger motion thrusts the stock endwise against the counterweighted stops 60 until it is matched endwise, after which the stops yield and permit the stock to pass with a quick movement into the lower mill pass over the guide table 68. Meanwhile the elements 50, 5!, 52, 53 and 54 have resumed initial position in which they are shown ready for the next unit of stock from the furnace and the stock unit being rolled will be delivered after its first pass to the catcher.

The catcher, which is fully described in application Serial No. 566,230, to which reference is made for details of construction and operation, may be briefly described as comprising upper and lower coacting sets of conveyor chains 10 and II, respectively mounted to travel in suitable upper and lower channel guides 12 and 13 which are spring-pressed together to cause these conveyors to frictionally grip the," sheet stock between them. The conveyor chains are driven through meshing gears M and i5 by means of a sprocket chain 16 from a motor 11 having a reversing control box 18.

The conveyors l0 and H are supported on a suitable frame work comprising an upper frame 19 for the chains 70 and a lower or main catcher frame 80 for the chains II which supports the upper frame 19 and in turn, near its lower center, is pivotally mounted on the stand 8I so as to permit the catcher to be rocked into position to coact with the upper or lower pass of the mill.

The catcher is rocked by connections comprising a link 82, a bell crank 83, and a link 84 which is connected to the piston of an air motor 85 having a three-way valve 86 for the admission of air pressure therethrough under control of a magnet 81 and an opposed coil spring 08. The stock delivered from the lower pass moves over a guide 89 and trips the arm 90 for flag switch 9| that controls the catcher circuits. As soon as the stock passes beyond the arm 9!! and releases it, the flag switch will energize the magnet 8'1, actuate motor 85 to swing the table upwardly into position opposite the upper pass, and reverse the motor 11 and chains 10 and II so as to return the stock over guide 89 into the upper mill pass. The upper frame 19 carries a retractable top stock guide 92 controlled by a trip arm 93 and a stop 94 on the mill stand, a spring 05 acting to retractthis guide sufficiently to clear roll I2 as soon as the trip 93 moves away from its actuating stop 94.

The stock thus reversed and returned from the catcher will again trip and release switch arm 90 causing the catcher to be swung to lowered position and its conveyor chains reversed so that they are ready to receive the stock when it is again returned to the catcher through the lower pass.

The stock emerging from the upper pass is carried over a guide I through pinch rolls IM and delivered onto a conveyor I02, constantly driven in the direction of the arrow by a suitable drive I03 from the motor I04, which will return the stock under the lower pinch roll and over guide I to the lower pass of the mill. After making the third pass, assuming that the three passes are all that are required, the finished sheets again enter the catcher and trip and release switch 90 for the third time in a cycle. This movement of the arm 90 will be without effect through the flag switch on the motor for tilting the catcher and driving the conveyor chains thereon, and hence the latter will continue to be driven in a direction to discharge the finished sheets onto a receiving table H0 connected by means of elements III and H2 to the catcher table and pivotally mounted at H3 on a stand H4.

This table H0 carries an endless conveyor chain I I5 driven in the direction of the arrow by a driving connection H6 and this conveyor will receive the finished stock and carry it to any suitable piling mechanism, not shown.

If the stock is to be given five passes, the trip and release of the arm 90 by the stock entering the catcher after the third pass will, in conjunction with the screw-down mechanism, set up circuits which again act to rock the catcher upwardly, reverse the motor 11 and chains I0, II and return the stock for its further pass through the mill. The stock after its final pass'again trips and releases arm 90, but this time without efiect on the catcher or its conveyors, so that delivery of the stock is made to table H0, as above described.

The delivery and return of the stock for the various passes makes necessary the provision of means to operate the screw-down mechanism so that the rolls will be quickly and accurately set to give the roll clearance required for each ass. We propose to control the screw-down operating mechanism so that the adjustments of the rolls will be automatically and accurately effected.

In application, Serial No. 586,223, a detailed description is given of the automatic control for the screw-down. It may be briefly described as follows, reference being had to Fig. 5. As the stock is carried by the feed table to the lower rolls, the screws are in their raised, or first position, and are lowered to their second position when the flag switch 9| is actuated by the stock passing into the catcher table. The switch 9| on release of arm 90 sets up a circuit to the motor 25 which continues to operate until the arm 21 opens switch 28 and moves on far enough to open the switch 28a. As the stock returns to the upper feed table through the upper rolls, it again actuates the switch 9| which setsv up a circuit to the motor to lower the screws to their third position ready for the third pass of the stock back through the lower rolls, the motor being stopped by the arm 21 opening the switch 28b.

As the stock moves into the catching table after the third pass, it again actuates the switch ill to set up a circuit to the motor 25 to lower the screws for the fourth pass of the stock through the upper rolls, the motor circuit being broken by the arm 21 opening the switch 200.

As the stock leaves the catcher table for the fourth pass through the upper rolls, the switch 9| is actuated to set up a circuit to the motor 25 to lower the screws for the fifth and final pass of the stock through the lower rolls and onto th catcher table, the circuit to the motor 25 being broken by the arm 21 opening the switch 28d.

As the stock moves into the catching table after the fifth and final pass, it actuates the switch 9| to set up a circuit in a reverse direction through the armature of motor 25 to move the screws upwardly to their first position. As the control arm 21 travels back in the reverse direction it resets each of the switches 28d, 28c, 28b, 28a and 28 successively, causing the motor to stop when the switch 28 is actuated.

It will be observed that the motor 25 is started up immediately after the stock leaves the lower pass, but a delayed action is necessary to prevent the motor starting up after the release of the switch arm 00 on the return passes, until the stock will have had time to clear the upper pass. All these control operations are timed so that no time will be lost and the stock can be given as many as five passes without being reheated.

The circuits and automatic control mechanism for the feed table are illustrated in Fig. 3 and briefly described as fc1low:-:When flag switch 5| is in its normal position shown and main switch 200 is clozed, relay A is energized through a circuit 20I, switch FSI, relay A, and leads 403 and 202, and being of the retarded type it will hold switch AI closed a sufiicient length of time, after switch FSI is opened, to permit a circuit to be completed to relay B and through swimh BI to the magnet 51. When the stock trips arm 50 it opens switch FSI and closes switches F82 and FSE. PS2 on closing completes a circuit to relay B through 2!, FS2, 204, AI, 205, B, 205 and 202, closing switch BI to complete a circuit to magnet 51 through leads 20I and 201, El, lead 208, magnet 51, and lead 202. After this magnet solenoid 51 operates the side matching bars 44 to align the sheet stock, the retarded relay A will open AI deenergizing relay B opening BI and deenergizing magnet 51, whereupon the spring resets valve 56 causing matching bars 44 to be retracted and stops 43 to be unlatched, so that the stock will advance to stops 60. The ram operation then occurs as follows:When the stock actuated flag switch 5|, a circuit was completed to energize relay C through 20l, FS3, 209, D2, 2l0, C, 206, and 202. A holding circuit is provided for the relay C through 20l, 201,,Cl, 2, 209, D2, 2"), C, 206 and 202, to hold this relay energized after the stock has passed and released arm 50 and the flag switch 5| has been returned by springs 220 to its normal position.

Retarded relay E, normally energized through circuit 20l, 201, C2, 2l2, D3, 2l3, E, 203 and 202 will close switch El, at a predetermined time after switch C2 opens, to energize relay D through a. circuit 20l, 2l4, screw-down control switch 283, 2l6, El, 2l1, D, 206 and 202. Relay D then closes a circuit to the pusher valve control magnet 61 through leads 20l, 2l4, 2l8, Dl, 2l9, magnet 61 and lead 202. This causes the pusher valve to be operated to actuate the ram head. After the stock completes the first pass it actuates the screw-down and when arm 21 on the screw-down opens switch 283 the relay D is deenergized,

pusher valve 66 is reset by its spring, the ram head is retracted, and the automatic control is set for the next cycle, and cannot resume operation until the screw-down mechanism returns to initial position and again closes switch 228.

A suitable mechanism for carrying out under automatic control the various operations of the catcher in each cycle is illustrated in Fig. 4, which shows in diagrammatic form the switch and circuit mechanism which operate responsive to switches controlled by catcher trip arm 90 and the screw-down trip arm 21 as follows:--

Assuming main switches 303 and 305 closed and screw-down switch 28 in the position shown closing switches 28l and 28112, the relays G, H and J are deenergized and relay F is energized through the circuit 3l3, 28l, 3l4, 28112, F, 3l6, 3l8 and closes its switches Fl and F2. When F2 closes a holding circuit for F is established through 3l3, F2, 3l4, 28d2, F, 3l6, 3l8.

When the main line switch 305 is closed, cur.- rent flows over circuit 300, 306, Hl, 301 solenoid 388 of reversing switch 18 to 30l, causing switch 18 to supply current to motor 11 to drive the catcher chains 10 and H so as to move the sheets away from the mill.

The sheets entering the catcher throw arm 90 clockwise, closing the catcher flag switch FSli to close a circuit 3l8, 32l, J, 322, FS6, 323, 324, Gl, Fl and 3l3. Relay J closes its three switches. When arm 90 is released by the passing sheets,

it is returned to normal position by springs 302,

opening F56 before which a holding circuit for relay 'J is established through 3l8, 32l, J, Jl, 324, Gl, Fl and 3l3, and switches Jl, J2 and J3 are held closed. This return of arm 90 to normal position also closes a circuit through 3l8, re-

tarded relay H, 321, J3, 328, F84, 326, Fl, 3l3

to cause relay H to open Hl, deenergizing solenoid 308, and to close H2 and H3. whereupon, H2 closes a circuit to "solenoid 329 through circuit 33l and 332, and actuates switch 18 to reverse the current to the fields 333 of motor 11 and effeet a reverse drive of the chains 10, 1|. At the same time H3 completes a circuit to the table tilt ing solenoid 81 through circuit 336, 331 and ac tuating valve 86 to cause motor 85 to tilt the catcher upwardly to return the sheets to the upv per pass of the mill.

maining closed. FS5 will close a circuit to relay J through 3l3, Fl, 326, F55, 323, Jl, J, 32l and 3l8. This holds relay J energized and its switches closed.

FS1 on closing will energize relay G through a circuit 3l3, Fl, 326, FS1, 338, G, 339, J2, 34l and 3l8, whereupon relay G opens GI and closes G2."

When G2 closes a holding circuit is established to relay'G through 3l3, Fl, 326, G2, G, 339, J2, MI and (H8. When J3 and Fl close, relay H is energized over 3l3, Fl, 326, FS4, 328, J3, 321, H, 3l8.

When trip arm 90- resumes normal position after the sheets clear it on their return through the upper or second pass, it opens FS5 and FS1. When FS5 opens, it deenergizes relay J opening all of its switches with the following results: J2 breaks the circuit to relay G opening G2 and closing Gl; J3 breaks a circuit to retarded relay H which, after an interval allowing the sheets to clear the upper pass, opens H2 and H3 and closes Hl; H3 opens a circuit to table tilting magnet 81 causing catcher to tbe lowered; H2 opening, de-

energizes the motor reversing coil 329; Hl closing energizes motor reversing coil 308reversing the motor 11 and chains 10 and N.

All relays except F are now deenergized and the catcher will repeat the operations described for the third and fourth passes of the stock. On the fifth or last pass however, the screw-down trip arm 21 will have opened switch 28412 deenergizing relay F so that the arm 90 as it moves responsive to the passage of the finished stock over it will not act on the relays G, H and J and as a result the motor 11 will not be reversed, magnet 81 will not be energized and the chains 10, 1| will continue to travel away from the mill so that they will deliver the finished stock to the delivery table conveyor I I5 for piling.

The release of arm 90 will act to reverse the screw-down motor 25, as will be later described, causing trip arm 21 to reset switches 28 and 28d to the position shown in Fig. 4 and thus leave the catcher control ready for the next rolling cycle.

The circuits for efiecting the automatic adjustment and reversal of the screw-down mechanism are fully described in application No. 586,223 and will be briefly described by reference to Fig. 6 in which the trip arm 90 is shown associated only with those switches of fiag switch 9| which control the screw-down circuits.

The switches and relays stand in the position assumed when the screw-down is set for the initial pass. 0n closing main line switch 400, all

relays K, L and M are deenergized, and remain so during the first pass. When the stock enters the catcher from the first pass, it throws arm 90 clockwise, opening switch FS8, closing F39, and leaving FSl0 closed. This energizes relay K through circuit 40l, 405, PS9, 2, FSIO, 4l3, K, M4, L2, 402, whereupon relay K is held energized by a holding circuit 40l, 406, K3, 2, FSl0, M3 to relay K. Upon release of trip 90 by the passing stock, switches FS8 and FSIO stand closed and F89 is open. Through FS8 the relay M is energized by the circuit 40l, 405, FS8, 4l6 K2, 4l1, 2LSl, 4l8, 3LSI, 4l9, 4LSl, 42l, 5LSI, 422, relay M, 423, Ll, 402, and upon closing relay M establishes its own holding circuit through 40l, M2, 424, K2, 4l1, 2LSl, 4l8, 3LSl, 4l9, 4LSl, 42l, 5LSI, 422, relay M, 423, LI, 402.

The switches M3 and M4 when closed establish a circuit to motor 25 over 40l, M4, solenoid 421 .set the rolls for the third pass.

of magnetic brake 26, 428, motor 25, 429, M3, 402, causing the motor to set the screw-down for the second pass and in doing so to move trip 21 to open switches 28 and 28a.

The switches ILSI and 2LS2 will now be closed and 2LS1 will be opened, breaking the circuit to relay M, opening M3 and M4, and causing the motor 25 to stop and brake 26 to be applied.

As the stock is returned from the catcher for the second pass, it throws trip arm 90 counterclockwise, opening FS8 and F810 and leaves FSS open. 4

Upon the opening of FSIO, the circuit to relay K is broken, opening switches K2 and K3. When trip arm 90 resumes normal position, it closes F38 and FSIO. whereupon F88 closes a circuit to relay M through 401, 405, FS8, 416, KI, 431, 2LS2, 418, 3LSI, 419, 4LS1, 421, 5LS1, 422, relay M, 423, L1, 402. The relay M then again closes M3 and M4 and the motor 25 is again started to Trip arm 21 then throws switch 28b to open 3LS1 and close 3152. When 3LS1 opens, it breaks the circuit to relay M, and by opening M3 and M4 the motor is stopped with the rolls set for the third pass.

The stock, after the third pass, trips arm 90 clockwise and energizes relay K as described, and when arm 90 resumes normal position, relay M 'is energized over circuit 401, 405, F88, 415, K2, 4", 432, 3LS2, M9, 4LSI, 421, 5131, 422, relay M, 423, L1, 402. The motor 25 is started again and sets the rolls for the fourth pass, and is cut out by trip arm 21 throwing switch 28c and opening 4LSI to deenergize relay M.

The return of stock for the fourth pass first moves trip arm 90 counter-clockwise to open FSIO and deenergize relay K. When arm is released, relay M is energized over circuit 401, 405, FS8, 416, Kl, 431, ,2LS2, 418, 4LS2, 421, 51,31,422, relay M, 423, L1, 402. This energizes motor 25 to set the rolls for the last pass and trip arm 2'1 stops the motor by throwing switch 28d to open LS1 and deenergize relay M.

On the last pass, the stock throws arm 90 clockwise to complete a circuit to relay K and then releases the arm 90 to resume normal position and energize relay L over circuit MI, 405, FS8, 416, K2, 411, 432, 3LS2, 419, 5182, 433, ILSI, 434, relay L, 436, M1, 402.

When relay L is energized it closes switches L4 and L5 and through them establishes a reverse circuit to the motor 25 through 401, L4, 429, motor 25, 428, 426, L5, 402, which resets the rolls for the initial pass and causes trip arm 21 to reverse all the switches 28d, 28c, 28b, 28a and 20. When switch 28, is reversed, it opens the circuit to relay L and stops the motor, leaving the relays and rolls set as first described.

It will thus be seen that by the instrumentalities described, we obtain a full automatic control of the complete multipas's rolling of stock by a single stand of rolls, and since the timing of the clock is such that there will be but little delay of the hot stock on the feed table before the screwdown is ready torelease the stock to enter the first pass, and since this feed of the stock is accomplished very quickly by the power ram, and its subsequent passing back and forth through the mill is accomplished quickly and without any delays, the complete rolling cycle can be completed even for five passes without necessitating a reheating of the stock. We have sought to describe herein only one suitable system of auto-' matic control mechanism, but we are aware that the control system may be widely varied as to its details without, however, departing from the essentially novel features of our invention and its cycle of operations.

While we have shown our invention in but one form, it will be obvious to those skilled in the art that it is not so limited, but is susceptible of various changes and modifications, without departing from the spirit thereof, and we desire, therefore, that only such limitations shall be placed thereupon as are imposed by the prior art or as are specifically set forth in the appended claims.

What we claim is:-

1. A continuous rolling mill comprising in combination a continuous heating furnace forthe stock to be rolled, automatic means for periodically discharging heated stock from said furnace, a feed table for the rolling mill disposed to receive and operable to deliver the stock to the rolls, a stand of arfiustable rolls, a screw-down mechanism for regulating the pass clearance between the rolls, a catcher mechanism adapted to receive and return the partly rolled stock to the feed table and to discharge the finished stock, and control means to accomplish the automatic operation and cooperation of the screw-down and catcher mechanisms.

2. A mechanism according to claim 1, in which the feed table comprises means to restrain the initial delivery of heated stock to the rolls, and the control means comprise elements adapted to release said stock restraining means responsive to the return of the screw-down mechanism to initial position.

3. A mechanism for-the automatic back and forth movement of stock for a series of passes through a stand of rolls, comprising a mechanical stock feed mechanism on the front side of the mill, a mechanical catcher on the back side of the mill, a screw-down mechanism for adjusting the pass clearance for the mill rolls, and means responsive to the screw-down mechanism for automatically and selectively controlling the return or discharge of stock by the catcher.

4. A mechanism for the back and forth passage of stock through a rolling mill, comprising in combination a catcher having reversible means to discharge rolled stock or return it to the feed side of the mill, a screw-down mechanism for regulating the roll pass clearance for each pass of the stock, and means automatically controlled by the screw-down mechanism and the movement of the stock to cause the catcher to return or discharge the stock.

5. In a mechanism for the continuous rolling of sheet stock by a single stand of rolls, a feed table, mechanism to arrest the stock on said table, mechanism to match the stock, mechanism to release the matched stock for initial delivery to the rolls, mechanism to receive stock returned from the catcher side of the mill and return it to the mill for another pass, a screw-down mechanism, and mechanism automatically responsive to the screw-down mechanism for controlling the release of the new stock by the feed table and the discharge of finished stock.

6. In combination, in a sheet hot rolling mill, a continuous heating furnace for supplying heated stock for the mill, automatic means for effecti g a periodic discharge of heated stock from said furnace, a screw-down mechanism for the rolls, and means for delivering the heated stock to the mill pass automatically responsive to the screw-down mechanism resuming position for the initial pass.

'7. In combination, in a sheet hot rolling mill,

9. continuous heating furnace for supplying heat= ed stock for the mill, automatic means for effecting a periodic discharge of heated stock from said furnace, a screw-down mechanism for the rolls, means for delivering the heated stock to the mill pass automatically responsive to the screwdown mechanism resuming position for the initial pass, means to arrest the heated stock adjacent .to the rolls, and means to receive rolled stock returned to the feed side of the mill and again deliver same to mill in a manner to avoid interference with heated stock waiting to enter the mill for its initial pass.

8. In combination a multiple-pass mill and means located on the entering and exit side of said mill for feeding stock thereto in one pass and returning said stock in another pass during the continuous unidirectional movement of the rolls of said mill, automatic means operable in connection therewith for discharging a piece at the end of a predetermined number of passes, power means for operating the screw-down of said mill and automatic means for controlling the operation of said power means, in accordance with the passage of the piece through said mill; means for delivering a piece into a position for entrance in the said mills and means for releasing said piece to said mill and automatic means for actuating said releasing means automatically responsive to the completion of a cycle for the preceding piece.

9. In combination a multiple-pass mill and means located on the entering and exit side of said mill for feeding stock thereto in one pass and returning said stock in another pass during the continuous unidirectional movement of the rolls of said mill, automatic means operable in connection therewith for discharging a piece at the end of a predetermined number of passes, power means for operating the screw-down of said mill and automatic means for controlling the operation of said power means, in accordance with the passage of the piece through said mill, a furnace, means for removing a second piece from said furnace and for delivering said piece in posi- 7 its passage through the mill and return it.

through a difierent pass, means distinct from said first mentioned feeding means to return the stock through the mill in the direction of the first pass comprising a tilted table provided with a feed belt continuously moving in a direction contrary to that of the stock approaching it.

11. In a multiple-pass mill for the continuous rolling of sheet stock by a single stand of mills, having means located on the entering sideof the mill for feeding heated stock thereto, and means located on the exit side to catch said stock after its passage through the mill and return it through a difierent pass, means distinct from said first mentioned feeding means to return the stock through the mill in the direction of the first pass comprising a tilted table provided with a feed belt continuously moving in a direction contrary to that of the stock approaching it, a guide and pinch rolls to conduct the stock from the rolls onto said feed belt, one of said pinch rolls coacting with the said feed belt to provide additional means for urging the stock back into the original pass.

ALBANUS GROOME DELANY.

GUY NEWTON HUGHES. 

